Add a rotary encoder

variants/heltec_rc32/HeltecRC32RotaryInput.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <helpers/RefCountedDigitalPin.h>
+#include <helpers/ui/RotaryInput.h>
+
+class HeltecRC32RotaryInput : public RotaryInput {
+public:
+  explicit HeltecRC32RotaryInput(RefCountedDigitalPin* periphPower = nullptr) : periph_power(periphPower) { }
+
+  bool begin() override;
+  RotaryInputEvent poll() override;
+  bool isReady() const override { return ready; }
+
+private:
+  bool writeRegister(uint8_t reg, uint8_t value);
+  bool readInput(uint8_t& value);
+  RotaryInputEvent handleTransition(uint8_t newState);
+
+  uint8_t input_state = 0x03;
+  uint32_t last_event_ms = 0;
+  bool ready = false;
+  bool initialized = false;
+  bool power_claimed = false;
+  bool active_low_phase = false;
+  RefCountedDigitalPin* periph_power = nullptr;
+};